One New Aftermarket Replacement Speed Change Governor Spring span stylefontsize14pxfont faceArialbFits John Deere Tractor ModelsbB sn 201000 and up, R w Pony motor, 50, 520, 530 fontspanfont faceArialbspan stylefontsize14pxReplaces Part Numbers spanbspan stylefontsize14pxENH500001, B2636Rspanb bfontpcenter.